In conventional designs, a ceiling fan with lights includes a light device mounted to a fan device, while the light device usually includes a metallic light board that is made from aluminum and that is connected to a neutral terminal of an AC (alternating current) power source, which is also connect to a neutral terminal of the fan device. However, when the light device is turned off and the fan device still operates, rotation of a motor of the fan device may induce a current noise flowing into the light device via the connection of the neutral terminal of the fan device and the metallic light board, resulting in abnormal illumination/flashing of the light device.